Metformin Drives Hepatocyte Molecular Reprogramming Through a Fibroblast Growth Factor 1-Fibroblast Growth Factor...

Cholestatic liver fibrosis involves a pathologic shift from hepatocyte to cholangiocyte molecular signatures. Metformin has hepatoprotective effects, but its impact on this shift remains unclear. We investigated whether metformin reverses this pathologic program and elucidated the underlying mechanisms.

We employed purified hepatocyte organoids derived from bile duct ligation and Mdr2^-/- mouse models of cholestasis, as well as patient-derived organoids. Transcriptomic and functional analyses were performed to assess metformin-induced molecular changes. Gain- and loss-of-function studies, including hepatocyte-specific Fgf1 knockout mice and fibroblast growth factor receptor 4 inhibition, were used to dissect the signaling axis.

Metformin reversed the pathologic gene expression profile in liver organoids, restoring hepatocyte-associated transcripts while suppressing cholangiocyte-associated transcripts, and concomitantly elevated T-box transcription factor 3 expression in both bile duct ligation and Mdr2^-/- models. This molecular effect correlated with upregulation of the fibroblast growth factor 1-fibroblast growth factor receptor 4 signaling axis. Gain- and loss-of-function studies confirmed that fibroblast growth factor 1 is sufficient to drive T-box transcription factor 3 expression and promote the hepatocyte-associated gene program, whereas fibroblast growth factor receptor 4 inhibition partially suppressed these effects and exacerbated fibrosis. Strikingly, the prohepatocyte molecular state induced by either metformin or fibroblast growth factor 1 in vivo was retained in ex vivo organoids, indicating durable, cell-intrinsic reprogramming. Genetic ablation of hepatocyte-derived Fgf1 partially abolished metformin's ability to induce T-box transcription factor 3 and the hepatocyte gene program, establishing a necessary and autonomous role for fibroblast growth factor 1. Crucially, in patient-derived organoids, both metformin and fibroblast growth factor 1 upregulated T-box transcription factor 3 and promoted a hepatocyte molecular program in a fibroblast growth factor receptor 4-dependent manner.

The metformin-fibroblast growth factor 1-fibroblast growth factor receptor 4-T-box transcription factor 3 axis licenses durable molecular reprogramming favoring a functional hepatocyte state, providing a mechanistic foundation for promoting liver repair in cholestasis.